The present invention relates to a modular stent graft composed of two stent graft modules for insertion into a blood vessel of a patient.
Stent grafts are generally understood as endoluminal prostheses or intra-vascular implants that are used in weakened, damaged, torn or aneurysmal vessels. For this purpose, a stent graft is released at the diseased or damaged site in the vessel and restores the functionality of the original vessel or supports the still existing integrity of the vessel. The stent graft, which is radially expandable, is for this purpose inserted into the vessel concerned and is radially enlarged or expanded.
Stent grafts are generally composed of a tubular, i.e. hollow cylindrical main body made of a biocompatible graft material, to which one or more stents or stent rings are attached. The stents presently used in the stent grafts are usually self-expanding and comprise what is called a shape-memory material, for example Nitinol, by means of which the whole stent graft is able to change from its non-compressed state to a compressed state and then, i.e. after release, can expand again to the non-compressed state. For insertion into the blood vessel to be treated, the stent graft is thus compressed and, in the compressed state, is inserted into the vessel until it comes to lie at the desired location. It is released there, i.e. it is allowed to expand to the non-compressed state. The walls of the stent graft then position themselves on the vessel wall and replace and/or support the latter. In this way, the defect is closed, and the blood carried in the vessel can flow through the tubular main body of the stent graft.
Stent grafts or vascular implants can generally be composed of a single stent graft body or, alternatively, of a plurality of separate but connectable stent graft bodies or stent graft modules. A modular stent graft has the advantage that it can be put together in a manner specific to the vessel/vessel area to be treated with the stent graft and to the different diameters or lengths of said vessel/vessel area. The individual separate modules of the stent graft are then generally inserted and assembled in situ, i.e. at the site to be treated in the vessel, so as to form a continuous stent graft. For this purpose, use is generally made of the fact that the ends of the individual stent graft modules overlap, and that one end of one stent graft module can be inserted with an overlap into one end of another stent graft module. As a result of the self-expanding force acting outward and in the direction of the vessel wall, the modules remain connected to one another in the overlapping areas by means of frictional forces.
Given the particular nature of the vessels to be treated in each case, prostheses are in many cases made available that are specifically tailored to the patient or to the vessels of the patient, in particular to the specific vessel to be treated, in order to meet the requirements concerning the necessary or desired length and diameter. This special and specific production is complex, expensive, labor-intensive and cost-intensive, since only one specific prosthesis can be produced in each case.
Therefore, there is still in principle a great need for prostheses that permit flexible use in order to meet the various requirements, particularly in terms of length and diameter, of the vessels of different patients. An object of the present invention is therefore to make available an alternative prosthesis system by which a tailor-made system, in particular a tailor-made system with respect to vessel length and diameter, is rendered superfluous.